melanocortin signalling comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-12-12. Numbers and descriptions here follow the published literature rather than marketing material.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
| Property | Value | Notes |
|---|---|---|
| Typical purity | 95% or higher | By reversed-phase HPLC area |
| Identity method | Electrospray mass spectrometry | Confirms molecular mass |
| Purity method | Reversed-phase HPLC | Detection near 214 nm |
| Primary degradation | Methionine oxidation | Sulfoxide product, +16 Da |
| Solution storage | 2-8 °C, short term | Aliquot to avoid freeze-thaw |
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
== Methods == There is a range of IQF technologies, but the main concept is to transport the product into the freezer with the help of a processing line belt or infeed shaker. Inside the freezer, the product travels through the freezing zone and exits the other side. Product transport inside the freezer uses different technologies. Some freezers use transport belts similar to a conveyor belt. Others use bed plates that hold the product, and an asymmetrical movement makes the plate advance by itself through the freezer. There are two main IQF technologies: mechanical IQF freezers and cryogenic IQF freezers. Mechanical IQF freezers work on the principle of cold air circulation, which flows from underneath the bed plate or transport belt with the help of fans. The cold airflow passes through the pieces of product in circular motions while the product is also advancing through the freezer towards the exit. The design and efficiency of this type of IQF freezers varies among manufacturers who seek to find the perfect balance of aerodynamics for an optimal freezing result. This technology has seen impressive improvements and developments during the past 20 years, being suited for an increasing range of products. Cryogenic IQF freezers immerse the product in liquid nitrogen at very low temperatures, freezing it rapidly while continuously moving the product to avoid block or lump formation. Although this method shows good freezing results, it might lead to higher processing costs per weight of product due to the cost of the liquid nitrogen required.
And although such interventions were later found to be ineffective for their intended purposes, those works led to the creation of tissue engineering, techniques for cardiopulmonary bypass and dialysis, established the foundation for the technologies for storing organs extracted from a person outside the body (which now are used, for example, during organ donation), the emergence of cryobiology. 1920s–1930s In medical practice, sex gland transplants were introduced to obtain rejuvenating effects. (Though separate experiments in this direction were done even earlier, even in antiquity.) The earlier mentioned operations of Dr. Frank Lydston in 1914 remained almost unnoticed. But the works of Leo Leonidas Stanley quickly received widespread scientific notice. Stanley was a physician at a prison in California and began to do these operations since 1919, using glands of executed criminals. In the following years, such operations were done by dozens of physicians (including Eugen Steinach) but they became most famous due to the activity of the French surgeon of Russian extraction Serge/Samuel Voronoff. It was believed that transplantation of sex glands provides more durable effects than injection of a suspension of ground glands. In case of transplantation from human to human, the glands of executed criminals were usually used. But due to a shortage of materials, the sex glands of young healthy monkeys were widely used, which were specially grown for this purpose (usually thin sections of the glands were implanted).
ubiquitination Also ubiquitylation. The labelling of a biomolecule (often another protein) by covalently attaching a ubiquitin protein to it—generally via the formation of an amide bond between the ubiquitin's C-terminal glycine and positively charged side chains (often lysine or arginine residues) of the labelled molecule, an ATP-dependent reaction catalyzed by ubiquitin-conjugating enzymes—thus making it identifiable to molecules capable of recognizing ubiquitin epitopes. Ubiquitination is a widely used post-translational modification by which proteins are tagged; the attachment of a single ubiquitin molecule (monoubiquitination) can variously activate or inhibit a protein's activity, while the attachment of a chain of multiple consecutively linked ubiquitin molecules (polyubiquitination) commonly targets the protein for degradation by proteasomes.
His method of testing won the Intel International Science and Engineering Fair Gordon E. Moore Award in the spring of 2012. The Boeing Company has patented the use of carbon nanotubes for structural health monitoring of composites used in aircraft structures. This technology is hoped to greatly reduce the risk of an in-flight failure caused by structural degradation of aircraft. Zyvex Technologies has also built a 54' maritime vessel, the Piranha Unmanned Surface Vessel, as a technology demonstrator for what is possible using CNT technology. CNTs help improve the structural performance of the vessel, resulting in a lightweight 8,000 lb boat that can carry a payload of 15,000 lb over a range of 2,500 miles. IMEC is using carbon nanotubes for pellicles in semiconductor lithography. In tissue engineering, carbon nanotubes have been used as scaffolding for bone growth. Carbon nanotubes can serve as additives to various structural materials. For instance, nanotubes form a tiny portion of the material(s) in some (primarily carbon fiber) baseball bats, golf clubs, car parts, or damascus steel. IBM expected carbon nanotube transistors to be used on Integrated Circuits by 2020.
== United Kingdom == Below are the individuals appointed by Charles III in his right as King of the United Kingdom with honours within his own gift and with the advice of the Government for other honours.
Sources: en.wikipedia.org
==== Using detrital zircon age abundance ==== In a global scale, detrital zircon age abundance can be used as a tool to infer significant tectonic events in the past. In Earth's history, the abundance of magmatic age peaks during periods of supercontinent assembly. This is because supercontinent provides a major crustal envelop selectively preserve the felsic magmatic rocks, resulting from partial melts. Thus, many detrital zircons originate from these igneous provence, resulting similar age peak records. For instance, the peak at about 0.6–0.7 Ga and 2.7 Ga (Figure 6) may correlate the break-up of Rodinia and supercontinent Kenorland respectively.
=== MSIR model === For many infections, including measles, babies are not born into the susceptible compartment but are immune to the disease for the first few months of life due to protection from maternal antibodies (passed across the placenta and additionally through colostrum). This is called passive immunity. This added detail can be shown by including an M class (for maternally derived immunity) at the beginning of the model.
== Professional career == Esimone started his career as internee pharmacist and then became a laboratory instructor, all in the Department of Pharmaceutics, University of Nigeria Nsukka. He became a professor of biopharmaceutics and pharmaceutical microbiology at the age of 37 years and was the pioneer Dean, Faculty of Pharmaceutical Sciences, Agulu Campus of Nnamdi Azikiwe University Awka. He also served two terms of 2 years each as the Deputy Vice-Chancellor (Academics) of Nnamdi Azikiwe University, Awka. He is a researcher with well over 100 publications and in May 2019 was ranked 18th on the list of 28 Most Published Scholars in Nigeria. Prof. Esimone was also the Director of Confucius Institute of Nnamdi Azikiwe University, Awka. On the 14 of May 2019 he was elected the new Vice Chancellor of Nnamdi Azikiwe University, Awka. He is the State Campus Coordinator for Deeper Life Campus Fellowship, Anambra State and also a member, BOT (Board of Trustees) of Anchor University, Lagos.
Multi-photon Raman spectroscopy, such as stimulated Raman spectroscopy (SRS) or coherent anti-Stokes Raman spectroscopy (CARS) help enhance signals from substances in microfluidic devices. A convenient approach for application of SERS-active metal nanoparticles is their embedding in gel-like particles or surface deposition on polymer micro particles. For droplet-based microfluidics, Raman detection provides online analysis of multiple analytes within droplets or continuous phase. Raman signal is sensitive to concentration changes, therefore solubility and mixing kinetics of a droplet-based microfluidic system can be detected using Raman. Considerations include the refractive index difference at the interface of the droplet and continuous phase, as well as between fluid and channel connections.
== Research == Azumolene is a 30-fold more water-soluble analog of dantrolene that also works to decrease the release of intracellular calcium by its action on the ryanodine receptor. In MH-susceptible swine, azumolene was as potent as dantrolene. It has yet to be studied in vivo in humans, but may present a suitable alternative to dantrolene in the treatment of MH.
Sources: en.wikipedia.org
In April 2024 doctors in Rafah performed a similar emergency c-section after an IDF bombardment targeted a housing block in Rafah, the baby survived in critical condition before dying after 5 days. Her mother, father and 3-year-old sister had all been killed in the bombing. In July 2024, yet another baby was delivered by surgeons after the mother was killed by an airstrike. The Women's Centre for Legal Aid and Counselling reported women were suffering from birth complications and a lack of both postpartum care and newborn vaccines. The United Nations Population Fund stated that newborn babies were dying because mothers were unable to access prenatal or postnatal care. According to a UNICEF State of Palestine Humanitarian Situation report, from early March 2024 at least 5,500 pregnant women do not have access to pre or post natal check ups due to the continued airstrike and lack of safe shelter. Doctors at the Al-Helal Al Emirati Hospital reported "chaos and suffering" due to the large influx of displaced people arriving to deliver their babies.
Some fish species have humps, with their makeup varying. The nuchal hump of a humpback chub (from which the species gets its name) is made up almost entirely of skeletal muscle, and may exist to reduce the chub's vulnerability to predators. The flowerhorn cichlid is an ornamental aquarium fish which is bred for its very large nuchal hump. Some breeders may artificially increase the hump's size by injecting it with hormones or feeding the flowerhorn a hormone-rich diet. Male salmon of the Oncorhynchus genus have dorsal humps, which were once thought to consist of cartilage, but is now known to be formed by increases in connective tissues and neural spine growth. Of this genus, sockeye and pink salmon develop the biggest humps, which are mostly made of connective tissue and which decrease in lipid content with age. In contrast, the closely related masu and chum salmon have smaller humps that are mostly formed by bone tissue.
=== Gene silencing === The PCSK9 antisense oligonucleotide increases expression of the LDLR and decreases circulating total cholesterol levels in mice. A locked nucleic acid reduced PCSK9 mRNA levels in mice. Initial clinical trials showed positive results of ALN-PCS, which acts by means of RNA interference. In 2021, scientists demonstrated that CRISPR gene editing can decrease blood levels of LDL cholesterol in vivo in Macaca fascicularis monkeys for months by 60% via knockdown of PCSK9 in the liver. In 2023, a clinical trial demonstrated that VERVE-101 gene therapy, which works via CRISPR gene editing, could reduce LDL cholesterol by as much as 55% in human volunteers with heterozygous familial hypercholesterolemia.
Since 1921, the Toronto Transit Commission (TTC) gradually expanded its public transportation network to Scarborough. Today, it operates bus and rapid transit routes in the district. Line 2 Bloor–Danforth has three subway stations in Scarborough: Victoria Park, Warden, and Kennedy, the current eastern terminus. In 1985, the Government of Ontario opened the Scarborough RT, an above-ground light metro line that operated between Kennedy station at its west and McCowan Road at its east. In 2023, the line shut down permanently due to aging Infrastructure which also caused a derailment earlier that year. Construction of an extension of Line 2 further east into Scarborough started in June 2021 and is expected to be complete around 2030. The line will be extended 7.8 kilometres from Kennedy station with stations at McCowan Road-Lawrence Avenue, Scarborough Centre, and McCowan Road-Sheppard Avenue. Opened in February 2026, Line 5 Eglinton is a light rail line with its eastern terminus at Kennedy station. The City of Toronto is also proposing another light rail line known as the Eglinton East LRT that is planned to operate from Kennedy station to the University of Toronto Scarborough. Seven rail stations also provide access to two commuter rail lines operated by GO Transit. The Lakeshore East line runs across the south end of the district with Rouge Hill GO Station, Guildwood GO Station, Eglinton GO Station, and Scarborough GO Station running from east to west.
Sources: en.wikipedia.org
Dry powder is normally held at -20 °C or lower, away from light and moisture. Sealed vials can also be kept at 2-8 °C for shorter intervals. Warming to room temperature before opening prevents condensation.
In solution, hydrolysis of peptide bonds and oxidation of the methionine residue are the principal concerns. Oxidation converts methionine to its sulfoxide form, shifting the mass by sixteen daltons. Both processes are slowed by cold storage and by avoiding alkaline conditions.
A certificate documents what the supplier measured on a specific lot, not how a laboratory will use the material. Independent verification of identity and purity is common practice. Acceptance criteria should be defined before a batch is ordered.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.